Sequence diagrams

The classic case, and PlantUML's native layout engine — no Graphviz needed.

OAuth authorization code flow (waiting to render)

OAuth authorization code flow

@startuml actor User participant "Browser" as B participant "Your app" as App participant "Auth server" as Auth database "Token store" as Store User -> B: Click "Sign in" B -> App: GET /login App --> B: 302 to auth server B -> Auth: GET /authorize?... Auth --> B: Login form User -> Auth: Credentials Auth --> B: 302 with code B -> App: GET /callback?code=... App -> Auth: POST /token (code) Auth --> App: access + refresh token App -> Store: Persist refresh token App --> B: Set session cookie B --> User: Signed in @enduml

Grouping, alternatives and notes

Retry with exponential backoff (waiting to render)

Retry with exponential backoff

@startuml participant Client participant Gateway participant Service Client -> Gateway: POST /orders group Retry up to 3 times Gateway -> Service: createOrder() alt success Service --> Gateway: 201 Created else transient failure Service --> Gateway: 503 note right of Gateway Back off: 1s, 2s, 4s end note end end Gateway --> Client: 201 Created @enduml

Lifelines, activation and self-calls

Order processing (waiting to render)

Order processing

@startuml participant Queue participant Worker participant Db Queue -> Worker ++: message Worker -> Worker: validate() Worker -> Db ++: begin transaction Worker -> Db: insert order Worker -> Db: insert line items Worker -> Db --: commit Worker --> Queue --: ack @enduml

Grouping, alternatives and notes
Lifelines, activation and self-calls

Grouping, alternatives and notes​

Lifelines, activation and self-calls​

Grouping, alternatives and notes

Lifelines, activation and self-calls